Magnesium alloy and production method of the same

Abstract

To provide a magnesium alloy having high incombustibility, high strength and high ductility together. A magnesium alloy including Ca in an amount of “a” atomic %, Al in an amount of “b” atomic % and a residue of Mg, including (Mg, Al) 2 Ca in an amount of “c” volume %, wherein “a”, “b” and “c” satisfy the following equations (1) to (4), and having the (Mg, Al) 2 Ca dispersed therein. 3≤ a ≤7  (1) 4.5≤ b ≤12  (2) 1.2≤ b/a ≤3.0  (3) 10≤ c ≤35  (4)

The invention claimed is: 
     
       1. A magnesium alloy:
 comprising Ca in an amount of “a” atomic %, Al in an amount of “b” atomic % and a residue of Mg, 
 comprising (Mg, Al) 2 Ca in an amount of “c” volume %, 
 wherein “a”, “b” and “c” satisfy the following equations (1) to (4), and 
 having said (Mg, Al) 2 Ca dispersed therein, 
 wherein a volume fraction of region of said dispersed (Mg, Al) 2 Ca is “f” %, wherein “f” satisfies the following equation (7), 
 wherein said (Mg, Al) 2 Ca is dispersed in a metallographic structure, and 
 wherein the region contains the metallographic structure
   3 ≤a≤ 7  (1)
 
   4.5 ≤b≤ 12  (2)
 
   1.2 ≤b/a≤ 3.0  (3)
 
   10 ≤c≤ 35  (4)
 
   35 ≤f≤ 65  (7).
 
 
 
     
     
       2. A magnesium alloy:
 comprising Ca in an amount of “a” atomic %, Al in an amount of “b” atomic % and a residue of Mg, 
 comprising (Mg, Al) 2 Ca in an amount of “c” volume %, 
 wherein “a”, “b” and “c” satisfy the following equations (1) to (4), and 
 having said (Mg, Al) 2 Ca dispersed therein, 
 wherein a volume fraction of region of said dispersed (Mg, Al) 2 Ca is “f” %, wherein “f” satisfies the following equation (7), 
 wherein said (Mg, Al) 2 Ca is dispersed in a metallographic structure, 
 wherein the region contains the metallographic structure
   3 ≤a≤ 7  (1)
 
   8 ≤b≤ 12  (2)
 
   1.2 ≤b/a≤ 3.0  (3)
 
   10 ≤c≤ 35  (4)
 
   35 ≤f≤ 65  (7).
 
 
 
     
     
       3. The magnesium alloy according to  claim 1 , wherein said magnesium alloy further comprises Zn in an amount of “x” atomic %, wherein “x” satisfies the following equation (20)
   0 <x≤ 3  (20).
 
 
     
     
       4. The magnesium alloy according to  claim 1 ,
 wherein said magnesium alloy further comprises Al 12 Mg 17  in an amount of “d” volume %, wherein “d” satisfies the following equation (5)
   0 <d ≤10  (5).
 
 
 
     
     
       5. The magnesium alloy according to  claim 1 ,
 wherein a crystal particle size of said dispersed (Mg, Al) 2 Ca is “e”, wherein “e” satisfies the following equation (6)
   1nm≤ e≤ 2μm  (6).
 
 
 
     
     
       6. The magnesium alloy according to  claim 1 ,
 wherein an ignition temperature of said magnesium alloy is 850° C or more. 
 
     
     
       7. The magnesium alloy according to  claim 1 ,
 wherein said “a” and “b” satisfy the following equations (1′) and (2′)
   4 ≤a≤ 6.5  (1′)
 
   7.5 ≤b≤ 11  (2′).
 
 
 
     
     
       8. The magnesium alloy according to  claim 7 ,
 wherein said “a” and “b” satisfy the following equation (3′)
   11/7 ≤b/a≤ 12/5  (3′).
 
 
 
     
     
       9. The magnesium alloy according to  claim 7 ,
 wherein an ignition temperature of said magnesium alloy is 1090° C. or more. 
 
     
     
       10. The magnesium alloy according to  claim 1 ,
 wherein when compression yield strength is “g” and tensile yield strength is “h”, “g” and “h” of said magnesium alloy satisfy the following equation (8)
   0.8 ≤g/h   (8).
 
 
 
     
     
       11. The magnesium alloy according to  claim 1 ,
 wherein said magnesium alloy contains at least one element selected from the group consisting of Mn, Zr, Si, Sc, Sn, Ag, Cu, Li, Be, Mo, Nb, W and a rare-earth metal in an amount of “i” atomic %, where “i” satisfies the following equation (9)
   0 <i≤ 0.3  (9).
 
 
 
     
     
       12. The magnesium alloy according to  claim 1 ,
 wherein said magnesium alloy contains at least one compound selected from the group consisting of A 1   2 O 3 , Mg 2 Si, SiC, MgO and CaO in an amount of “j” atomic % as an amount of metal atom in the compound, where “j” satisfies the following equation (10)
   0 <j≤ 5  (10).